Stroke Active Learning Flashcards
What is a stroke?
a sudden onset focal CNS deficit due to vascular cause
WHat is a TIA?
It’s a TRANSIENT neurologic dysfunction without evidence for cerebral infarct
it’s caused by focal brain, spinal cord, or retinal ischemia wihtout acute infarction
NO PERMANENT TISSUE DAMAGE
What is the difference between a TIA and a TSI?
A TSI is transient symptoms with infarction
So patients have symptoms that totally resolve, but they have a lesion on MRI - so basically a damaging stroke with no permanent effects
What are the two types of stroke? Which is more common?
hemorrhagic and ischemic (most common)
What are the vast majority of strokes caused by in the US?
atherosclerotic disease
What happens in an ischemic stroke?
a direct thrombosis or embolism from another source occludes a cerebral vessel, cutting off oxygen supply to the regions supplied by the vessel, leading to neuronal death and neurological deficit
How long does it take for neurons to start dying after osygen is cut off?
only 4 minutes
What are some other causes of ischemic stroke besides atheroscleotic disease? In what group are these most common?
vasculitis, sickle cell crisis, severe preeclampsia, vertebral or carotid artery dissection, complicated migraine with vasospasm, sympathomimetic induced vasospasm from drug use like cocaine or amphetamines
adults younger then 45 years of age
How can ischemic strokes be further classified?
large vessel or small vessel
What vessels are most often affected in anterior circulation? Posterior circulation?
anterior: 1. common carotid 2. MCA 3. ACA
posterior: 1. vertebral artery 2. basilar artery 3. PCA
What vessels are affected in smal vessel ischemic stroke and what’s the term for these strokes?
the penetrating arteries
called lacunar stroke
What past medical history factor is very much associated with lacunar stroke?
HTN
it induces endotheliual damage, such that the penetrating arteries have an increased risk of bleeding and clot formation
What is the difference between intracerebral stroke and subarachnoid hemorrhage morphologically?
intracerebral stroke is bleeding into the brain itself
subarachnoid hemorrhage is bleeding into the space between the arachnoid and the pia
How do intracerebral stroke and subarachnoid hemorrhage differ symptomatically?
intracerebral stroke involves sudden focal neurological deficits but no real headache
Subarachnoid hemorrhage includes thunderclap headache, LOC, focal neuro findings, nausea, vomiting, photophobia, nuchal rigidity, etc.
What percentage of strokes are intracerebral hemorrhage?
13%
What are the risk factors for intracerebral hemorrhage?
increasing age
male
HTN
EtOH
tobacco
diabetes
How do you diagnose a hemorrhagic stroke?
head CT
What is the current management for intracranial hemorrhage?
- STOP or reverse anticoagulants if they’r eon them
- surgical removal of clots may improve outcomes
- lowering BP maybe contribute to improved fucntion in survivors
What are subarachnoid hemorrhages usually caused by?
trauma and shear forces that tear the perforating vessels feeding the underlying ocrtex
more common in elderly because their brains have shrunk a bit
What is the most common NON-TRAUMATIC cause of subarachnoid hemorrhage?
ruptured berry aneurysm
What are the demographics of berry aneurysm rupture?
mean age 55
50% mroe common in men
blacks twice as often as whites
What is a symptom that can warn of a berry aneurysm?
sentinel headaches - during exercise or sex
If a head CT is inconclusive but you have high suscpicion for a subarachnoid hemorrhage, what other diagnostic test can you do?
do an LP and look for blood in the CSF
What drug can you give for SAH management?
Nimodipine
it’s a Ca2+ channel blocker that preferentially affects the CNS
we think it works to dilate small vessels to increase collateral circulation and preserve cerebral perfusion in the event of massive bleeding
